Now Worse After Removing Carbs

Update so far I have now removed inlet manifold it needed doing as rear seal was weeping. I have cleaned both faces on heads and manifold. I noticed that the inlet gasket was fitted wrong way round. Not sure if this will make any difference. Also noticed a gap in carb insulators. With this in mind I have ordered new carb gaskets from Wins which hopefully will arrive tomorrow. Also took the opportunity to get new throttle rod bearings as they are missing. Removed the plugs and tips are white so very weak mixture. I also got to check condition of pushrods and hydraulic lifters all look fine. However it doesn't look like its had many oil changes. So that's another job to do when I sort the running. I already have oil and filter. I have changed the air filters including the seals. What a job that is! New inlet gasket has arrived today. Does anyone know if it should have any sealer or does it go on dry. Once I get this back together this should eliminate any air leaks at front end. Thanks.
 
While you have it all open pull the plugs out and put a socket on the crank to turn the engine over while watching the rockers for equal travel. High time camshafts tend to end up with some rounded lobes with associated running issues.
 
As far as I can tell all seem to be equal. However now all back together and still the same. New fuel tap seal arrived today but still waiting for fuel pump kit. Cheap electric pump now arrived but now need to plumb in somehow. And to add insult to injury I have now lost choke cable connector from carb. I am beginning to think I should not have got this one.
 
How the hell does engine mounted reserve tap come off. I want to change the seal but the screw is solid. I don't want to damage it but cant see hoe to get at it. Also could fuel pump be left in place is I use an electric pump. Will fuel flow through it. I am thinking about fitting pump at back of engine. Maybe I could remove fuel feed from reserve tap and by pass it if I can connect fuel hose with a clip.
 
Soak it in WD40 or similar stuff and wait.
I would not leave the old mechanical pump where it is. You will get a blanking plate with gasket from Wins, MGBD etc for small money. Leaving it in place (and disconnecting the fuel pipes) it will still pump and I would expect damages then with plugs on in-and out connection. So, I would take it out.
Easiest conversion with electric pump on my opinion is to use (see Rockdemon´s advice) a puller-type pump, i.e. From Hüco. You simply disconnect ingoeing fuel line from the old mechanical pump and connect this line (new rubber piece please ) to the inlet of the new electric pump. Outgoing line from the pump to the carbs as with the old mechanical pump. I have mounted my Hüco right below the ignition coil. It must not be a Hüco, but one for carbs with low pressure (also SU / Burlen has such pumps). With this arrangement you can stay with the reserve tap.
With electric pump you need a suitable relay and it´s recommended to use a crash sensor (inertia switch ?) for safety cut-off.
If this procedure will cost you more hairs, stay with the mechancial pump and buy a service kit from Wins, MGBD.
Why do you want to change the pump ? Did you already test, if your mechanical pump will bring fuel ?
 
I have fuel starvation/ weak mixture so I am trying to get to bottom of this. Its drawing air somewhere so I am going through everything step by step. I am going to rig a temporary electric pump with a slave tank to see if that cures it. If it doesn't I'm stumped.
 
weak mixture often due to incorrectly set carbs but if we suspect air intake leak? this will have major effect both on fuelling and running and idle can be lumpy/surge etc
we can check for some air leaks by using bubbles in soapy water and spraying around suspect leak areas. if we get sudden change in engine tone? as water is sucked in . then we have an area to look at. if carb gaskets were not renewed ? when carbs off then we can have issue there. check small vacuum hose etc
soem even spray an flammable fluid around but NOT recommended. e.g. WD40 as when it finds 'leak' and gets drawn in revs rise . if its a bad leak we may even hear a 'sucking' sound when any fluid covers leak point temporarily.
all about slowly check form basics . e.g. timing?
bubbles in fuel filter cam indicate insufficient fuel supply or leak on supply side but can also be due to 'gassing' as most fuel now has higher 'E' numbers of bio added. ( not ideal for our cars) do let us know how things progress.
 
I have changed inlet manifold gasket all 4 carb gaskets. Changed plugs cap leads and rotor. Checked points and condenser also now fitted powerspark ignition module. Timing is at 6 degrees btdc as per books. it did start surging and missing. This is why I now suspect pump. I do have bubbles in fuel filter and there is hardly any fuel in filter. I have checked under car for evidence of leaks but all seems dry including fuel tap. I was going to change seal just to make sure. It will only just run on full choke and cuts out if I try to increase revs and it sounds like there is no fuel
 
If the pump is your suspect, I would take it out and use a service kit i.e. from Wins (it´s around 25 GBP), that´s the simplest way to make sure that pump is ok. I would disconnect fuel line after pump/before carbs and extend it into a can, then disconnect coil and start engine and watch fuel coming or not coming. Beside pump it could be lever between normal and reserve position (info from another member here) or finally blocking in your tank or fuel line before the pump. So, I think, fitting an electric pump is not necessary at this stage. My mechanical pump was fully ok with its 43 years and I simply changed it to have 0,01 hp more....
 
It could also be the Powerspark ignition. I fitted one on my P5B and it worked for 1,5 years and then started to fail intermittent. Now replaced with a Range rover distributor and the engine runs better and also occasional backfires are gone. I believe Powerspark states that they use original Lucas or BL components but i disassembled the distributor and parts are not interchangable between the Powerspark distributor and the Range rover one. When fitting the Powerspark distributor, i also fitted an uprated oil pump with a "male" connection so i am able to use the later distributors (SD1 and Range rover) without problems
Peter
 
Well I hooked up electric fuel pump and it made no difference. I t makes no difference if I use the Powerspark kit or points and condenser. The fuel runs freely from the tank when disconnected from fuel pump. This now only leaves ignition coil or carburettors. I am now thinking about getting them rebuilt as I am not confident I haven't got something wrong inside them. Failing this I do have a rather expensive garden ornament. Does anyone know of good carb specialists. Thanks.
 
Suppose, fuel runs also from pump to carbs, so I also think, it´s the right decision to take off the carbs and service them.
I´m not a carb specialist and it´s the first time I had SU carbs in front of me. They are ingeniously simple, you can do this. On each of the top bowl there´s a small aluminium "flag" with the ID No. of the carbs. Together with the general type (HIF6 ?) order service kits from Burlen. They come with a manual. You can find the manuals also on the Burlen homepage, so you can check, if this job is ok for you. I´ve googled also some better manuals with better illustrations (in German, so you will find more !), because some steps require good illustrations (adjusting the float-bowls, adjusting the jet heights, finding the correct position for the jet needles etc).
Before you dismantle the carbs, make photos from every side of them :rolleyes:
 
Not sure this is a job for me but dependant on cost I may have to try. I am desperate to get out in her again.
 
When you started here, you said, your car runs well. It sounds a bit irritating, but before you start with the carbs (which is worth in general on a 46 year old car), what did you exactly do since then ? You said, oil leak from the front seal, so did you take off the front timing cover etc ?
You´ve tried now so many things and I can understand the feeling very will thinking about home explosives in cars, but go to the first steps and check is cylinder 1 really on TDC if front pulley does show this, is your distributor on the right position with cyl 1, are your spark cables on the correct cylinders etc. Take a deep breath and start again.
 
I have not removed front cover. The car was running ok and then developed this fault. The only thing I had done at this point was change to Powerspark electronic ignition. When the fault started I reverted back to points and condenser. Remained the same. I have checked the timing and firing order all fine. The only thing I have not changed is the ignition coil. I am considering removing carburettors again and checking once more. Failing all of this I am at a loss of what to do next. I really appreciate everyone's input in trying resolve this problem but I am considering giving up altogether.
 
Did you replace the distributor cap and rotor arm with new items?
If so it may be worth substituting with another set, reason is that there are very cheapo ones about and cause very bad running problems.
Unless you can get new/ old stock items with Lucas on them try distributor doctor for the next best.
Clive.
 
You must log in or register to reply here.
Back
Top